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Old 24th Mar 2019, 12:13
  #2450 (permalink)  
Loose rivets
Psychophysiological entity
 
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Herod:
I stopped reading this thread a long time ago, but can someone explain a point to an old, retired 737 driver? All 737s pitch up with the application of power; it's a consequence of the design. This one will pitch up more than most; again a consequence of the design. If the crew are made aware of this, is it really beyond the power of the human mind to be ready and correct the pitch? In other words, no need for this system at all.
Further to jantar99's answer, there is a huge difference between the rotation caused by thrust, and the aerodynamic flight of the cowling. Having said this, it's hard to visualise this rotational force's causal airflow only being derived from the pre-stalling greatly increased AoA. But I can think of no other reason than that which jantar99 described. It's almost a parachute effect when you consider the vertical vector alone.

I can see the need to counter it, and do it automatically, but I suppose Boeing thought it would not come into play in the real world and the prime reason for MCAS was the technicality of certification. No need to mention it to anybody.

It's hard to believe there was a time when the same type, IIRC, 727, needed a stick push on one side of the Atlantic, but not the other.
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Last edited by Loose rivets; 24th Mar 2019 at 15:15. Reason: Forgot to quote-erize Herod's post
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